In a letter addressed to congressional leaders, Geithner said Treasury can take extraordinary measures to stretch the nation's checkbook by $200 billion, a move that normally would give the government two months leeway but because of the uncertainty about the "fiscal cliff," that would not be the case this time.

Geithner urged lawmakers to act to end the "significant uncertainty" in the nation's finances to prevent "default on ... legal obligations."

Geithner also warned the uncertainty could delay the filing of tax returns, exacerbating the problem.

Lawmakers and President Barack Obama are scheduled to return to Washington Thursday and resume negotiations to avert the "fiscal cliff," the effects of which will begin to be felt Jan. 1 unless a deal is reached.

Huge storm hits Ohio Valley, Northeast

NEW ORLEANS, Dec. 26 (UPI) -- A huge winter storm Wednesday spread from the Ohio Valley to the Great Lakes to the Northeast coast, U.S. forecasters reported. At least six people were killed.

Accuweather.com said the storm gave Little Rock, Ark., its snowiest Christmas in 86 years.

The weather disrupted air travel and forced the cancellation of Wednesday's scheduled basketball game between the Chicago Bulls and Indiana Pacers in Indianapolis, which had been blanketed by 7 inches of snow by midafternoon.

Severe winds blew the snow across Ohio and Indiana. Accuweather said the snow is expected to mount up to more than a foot across the interior of the Northeast. But rain and strong winds, and a sometimes icy mix, would hit the Northeast coast.

The report cited snow accumulations Wednesday morning of 14 1/2 inches four miles south of Marion near the southern tip of Illinois and 6 inches in Muncie, Ind., with more snow falling and winds gusting to 30 mph.

The National Weather Service said Christmas Day storms produced dangerous winds and tornadoes and left more than 190,000 customers without power.

Weather-related deaths killed at least six people in Louisiana, Oklahoma, Texas and Arkansas.

Morsi, in a televised speech, also acknowledged he has made mistakes since his election and called on opposition leaders to join in a dialogue on the country's future, the Qatari broadcaster al-Jazeera reported.

"The coming days will witness, God willing, the launch of new projects ... and a package of incentives for investors to support the Egyptian market and the economy," he said.

Ahram Online reported Morsi signed the document, which the Supreme Electoral Commission said was approved by 63.8 percent of voters in balloting the past two Saturdays.

The constitution was drafted largely by Muslim members of the Constituent Assembly. Opponents say it mixes politics and religion and have organized street protests against it. Morsi, however, said the document protects minorities sufficiently, denouncing the opposition as creating unnecessary turmoil.

Mohamed ElBaradei of the National Salvation Front, a former head of the U.N. nuclear watchdog agency, said the new constitution is an "interim" document. He said a new one should be drafted with contributions from all sides.

Syrian Army leader defects to rebels

ANKARA, Turkey, Dec. 26 (UPI) -- The head of the military police in Syria openly joined the rebels Wednesday, accusing the Syrian Army of war crimes against the people, including "massacres."

A statement by Lt. Gen. Abdulaziz al-Shalal was posted on YouTube, The Guardian reported. His location was not disclosed and the date of his defection was not clear, but some rebel sources told the British newspaper he was in Turkey.

"The army has destroyed cities and villages and has committed massacres against an unarmed population that took to the streets to demand freedom," he said. "Long live free Syria."

The BBC said al-Shalal had been suspected of aiding rebels since the uprising against President Bashar Assad's government began in March 2011.

In Syria, the Chinese ambassador, Zhang Xun, called for a negotiated peace between Assad and the rebels, Xinhua, the official Chinese news agency, said. Zhang met Wednesday with Lakhdar Brahimi, the joint envoy of the African Union and United Nations.

"China has always called for a political solution to the Syrian crisis and we will continue coordination and support to Brahimi's mission," Zhang said.

Aussie spies seek criminal immunity

SYDNEY, Dec. 26 (UPI) -- Australian spies say they want the same legal protection as undercover police if they are going to be asked to infiltrate suspected terrorist organizations.

Australia's covert Australian Security Intelligence Organization said undercover spies risk criminal prosecution if they receive training from a terrorist group, even if they are gathering intelligence to thwart potential attacks, officials said.

"If an ASIO officer or human source is tasked to collect covert intelligence in relation to a terrorist organization, they may be open to criminal liability under the Criminal Code if, in the course of collecting the relevant intelligence, they receive training from that organization," the Attorney General's Department told lawmakers.

An AISO spokeswoman told The (Sydney) Daily Telegraph undercover spies will occasionally have to engage in what would normally be considered illegal acts to fulfill the mission of infiltrating suspected terror groups. Agents deserve legal immunity from prosecution if they are carrying out orders, the agency said.

A report on the matter from a parliamentary committee is due next year, The Daily Telegraph said.

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